Lubricating composition and process for making the same



Patented Oct. 29, 1935 PATENV FFICE LUBRICATING COMPOSITION AND PROCESS1 FOR MAKING THE S A Carleton Ellis, Montclair, N. a, assignor toStandard Oil Development Company No Drawing. Application May a, 1932Serial No. 609,038

l3 The present invention relates to improved lubricating oilsparticularly those of high lubricating value of the petroleum type, andrelates especially My invention will be fully understood from thefollowing description of the product and its method of manufacture.

Various addition agents have been incorporated from time to time inlubricating oils for the purpose of increasing their load bearingcapacity or for other similar reasons. I have found, how.-

5 ever, that many of these agents while extremely efiective for someparticular combination of hearing metals are not equally desirable forother types of bearing combinations. The present invention is concernedwith a class of substances :0 possessing a property of notablesignificance, l. e., that of imparting to the lubricant a higher degreeof film strength in substantially all types of bearing combinations or,if in certain bearing metal combinations it is not substantially raised,at least 5 it may be said that the presence of these substances does notlower the film strength for such bearing'metal combinations, while otherproperties obtain as hereinafter disclosed. By this means the filmstrength generally is perceptibly 30 increased permitting the use ofsmaller bearing surfaces and enabling the journals or other types ofbearings to be operated under more severe conditions of load, speed andthe like. The compounds of this sort which are disclosed below thus 5favorably aifect the state of tension of the lubricating film and may betermed tensionizers.

Another valuable property of many of the materials disclosed belowis'Ithat they act as pour inhibitors. Lubricatingpils produced fromcrude oil, hydrogenated hydrocarbon oils and the like contain waxyconstituents in such amounts as to cause the oil to congeal or solidifyat relatively high temperatures within the range in which such oilscould otherwise be used as lubricants. Oils from paramn or mixed basecrudes in many cases solidify at 50 or even 75 F. for the heavier cutsand the lighter distillates often solidify as high as 30 or'40 F.

50 It is the practicein modern refineries to re centrifugal means, butall of those methods require expensive refrigeration.

0n the other hand, the invention is likewise applicable to oils whichhave not been dewaxed or oils to which, for one reason or another,paraflln Y 5 wax, ceresin wax, petrolatum and the like, has been added.

As stated above many of the substances disclosed below act not only inthe capacity oftensionizers but likewise exert a pour inhibitinginfiuence. Therefore, according to the preferred form of my invention Iutilize compounds which are capable of functioning in the dual role ofpour depressant and tensionizer and which may be designated as pourdepressant tensionizers or tensioniaing pour depressants.

The materials which form the basis of my in= vention arenitrogen-containing and of the class formed by the reaction of hydromvamines, particularly the alkylolamines such as methanol-,

ethanol--, propanol-, butanol and the higher hydroxy amines with anorganic acid, specifically the esters f'orme'd thereby which areadequately soluble in petroleum lubricating oils to function in themanner described above. I do not wish to exclude, however, as pourdepressants and/or tensionizers the salts of the amines such as formedby the simple addition of the acid to the amine and which reaction ischaracterized by combination without elimination of water; preferably,the products which fall within certain specific confines of the presentinvention are the true esters formed by the reaction of acids withhydroxy amines and characterized by the elimination of water. In suchcases amine salts, if desired, may 3 be present, or the product may atthe same time a be an amine salt and amino ester.

The said products may be obtained in the same manner in which trueesters are formed, for example, by mixing the alcoholic material, thatis 40 to say, the hydroxy amine in this instance, with the organic acidand efiecting the esterification,

for example, in the presence of sulphuric acid or other inorganic acidsin the ordinary, well-known manner, or the esterification may beaccomplished by heating the reactants at a temperature of 212 F. orsomewhat higher in the absence of mineral acids. Those methods are aptto produce a certain amount of the salt as well as the ester and if itis desired to produce only the ester, 3 mols of the acyl chloride may beheated with, for example, 1 mol of the trihydroxy amine in the presenceof a basic material such as pyrldine. In such case the hydrochloride ofpyridine is formed, and the esterof the hydroxy amine andthemeviemiyuxidizedmmnganmeandwbaitresinatemberimneimmmteandthem,mixtmeseimesemaw'iaism'otm-Wate assteaiieeleimbehmiem'emeiemaybemedasweiiastheheavierunsammtedaeidsermixturesoithesevmieusmafieriais.

Theseestemmagybedispemedthmughthewaxeontainingbyflmmflmneiibymeanswasohmasforexampiealeahei,benzme,naphiha,eramothersimiiarlightsnlveutcambieddimhnmg the esters and mixing wifli'thewaxy uiis. m solution of the esberiseddedte thewax-mininingoilwhiehisthenthurwgmyaaitatedmmrm a homogeneous name afterwhich the mperatureofthemixhiremayberaimdwsufliadegreeastobm'iofltheiw-bniiingsulvent withuutdeeempesingfliehmviereii.Emeferred the seiventmbeeminated ahogemer.andizhe-estermmedwiththeoilmetemhbby heatingtoabnntmr'. mthemtermybeaddedtoapertienoitheeiiimisfmmingemmcenhateswhieheanbeusedadvmmgemiswesadditions tothe oil stuck in suitable prelim-him'lheestermagbeaddedtotheeflmmdesiredpmpm'timierexampmbeiowmwemt 01'5 percent. 'Ihe-difiemtmhstanees vary somewhat in then new mime and/mmmsienizing puwemandwuseqmenmwmbeused insomewhat difierent; often-mmlto2pereentismemustdesh'ame. Eenemliyan 011mm 11mm fur- W ingstrength;furmflmmemimpominhibiterisusedtiiemaximmmpem-xeduetionisnetebteineiamatfliesamemeiftoogrmtaquamtyismdquamesufftheefl maybealteredtoadmundeflmhiefurmebesaiiithatthem m misneariyaiwayswifliintiiemngeflmmahomfllmmpercantandthemeperquanfltyofesiamquimdfurapartieuiaruilcanbemdmdetermimedhy test.

-Asanexampleufflieaeflmufsiihsmneesm aemrdingtomyinvmtimflieimwmgmbetakenasillusla'afive.lhetmsimiizingpourinhibitorismadeinthemnnerdmefihedabcwefromti'iethanoiamineandamixlm'em'aeidsebtainedbytheuxidafimofmmmbybbwingwitiairattempemmresutahmatwm 300F. Thetrieihamflammeandtmemdsamusedinfliemopertimufletflnemmemeheuf Gravity, 30.6"5. P. I. I

Viscosity (Subult) at PL, seconds. Viscosity (Saybolt) at 210 E, 45seconds. Pour, 31! F.

(150101 (Robinson), 10%. 10

when the mopnrtion of m added was 05pereentitwasfoundthatthesolidifieafinnpointoftheoil,30F.,was1edueedtol5F. Whmthe pour inhibitor was added in theproportion of aboutzpereenttothesamedLitspour mintfi wasreducedto-5F.Inboflicasesthedher above mentioned properties of the oil weresubstantiallyunehanmd. Theloadbearingcapaeilwoftheblendedoiiwastestedinm'speettovarimis difl'erent beuripg by theMongeyfll methodasdeseribedintheNafionaiPetmlmm News, November 11, 1931,page 47. Thefolhwing bearingeombinafionswereused:

Steeltobmnze.

Steeltoaluminum.

SteeitoBabbitt.

Steeltoeastiron.

Castimnmeestiron.

Castimntoalumimnn.

steeltosbeel. lnailotthmeeasestheblendedoflgaveexeellmtserviee.

While,ashasbeenindicated.diifmentmetalbearingcombinationsaiforddifieringdegresofserviee,itmaybenotedthatinthecaseofsteeltnahnninum,castirontoalmninmnandsteeltosteeLtheoilwithtensionizerafuremidgave emaderably better service thanthe untreated ails. Inflsinglargeramnuntsthan2peremtthepourinhihitmgpowerwassomewhatdim-M mished.ltispossihiehowevertoestahlishsimulmeouslyina'givmoil adequatempurtionsuftheeefiveamino compound.

Thepourinhibitorerpourdeprmntandlorfitensinnizermeybeprepaxedalsosimpiybyheazmgtheamineandurganicaeidtogetherwihhmitsuiphm'ieaeidorotherstmngaeidcataiystof wzm'ificatiei.Thisstepifdesiredmaybeearfiedoutin'flieoilitselforinaportionuithenlInthelattercase-awneentratecanbemepamd martothetindieatedabove.Oilwhiehisat a high temperature from some other mewieus eperationmayreceive additions of the componentsotthe pour depressant and/01'tensinnim, musmtivelytheaeidsfromuxidizedpammwax and triethanoiamine,reaction taking place in tmlmtvehieieandderivingthepmduetinaveryeenvemientmanner.

Ontheotherhandthepourdemmterten- 5o simiaermamiurexampleintheabseneeofanm'ldiinent suehasthat mentioned above,beur-Mmeentratedifneeessarytoahigherdegme e5 pofieney by.treatment withappropriate solvmtsizoseparateaimreizmveinmztiveorllesseefiveeomponeats.

ltshouldbe'mentionedaisuthatwithhydtmamiueseontainingtwourmorehydmxylgmu s m the molecule (polyhydr xyamines), sxeh asmemolamimimayalsomakeestersbymixingtiieamineandfattyaeidsinfhestoichinmetziem'oporfiunsoflpartotaminetolmnoiaeiiorleartofaminetoiipartsofaeiiinsteedeithemfieoflpmtofamineto3partsetaeid esgivmintheabove-esample. Furthemmflcrude acids obtained by the oxidation of paramn wax may befractionated, for example by means of vacuum distillation and a lowboiling or higher. boiling fraction used, ranging from liquid or softacid material to hard wax acids, as desired. In general the compoundscomprised herein preferably are derived from higher fatty acids and thelike including those the moleculeof which contains 10 carbon atoms andover. Wax acids embrace a wide range of acids as denoted by the numberof carbon atoms, whereas the acids derived from animal and vegetablefats possess carbon atoms from say 12 to 22 in number, the acidscommonly available being those of 12, 16, and 18 carbon atoms. Thesevarious fatty acids are comprised under the term higher fatty acids asused in the foregoing.

In addition' to the foregoing additions to lubricating oils inaccordance with the preferred form of my invention I also may addanti-oxidants such as certain bodies containing phenolic groups. Certainamino compounds also act as anti-oxidants and the amino compoundsincluded in the present invention serve for this purpose to the extentthat such function is available, but others may be added for additionaleffect. The addition of these substances may be made to an oil which hasbeen used so as to become slightly oxidized and is susceptible tofurther oxidation accompanied by sludge formation. These materials notonly reduce the susceptibility of the oil to further oxidation but alsomodify the oil by imparting to it a greater load bearing capacity andpour reducing properties as indicated above. My process serves as avaluable aid in the recovery of used lubricating oils. Afterconsiderable heavy service a lubricating oil develops acidity andsludge. The sludge may be removed in a variety of different ways, forexample by filtration which also removes metal particles and dirt;sludgy constituents which are not entirely removed by filtration can beremoved by adsorptive means such as by the use of fuller's earth and thelike. These methods will leave the oil. however, inan acid condition. Ifdesired I may add my alkylolamines directly to this oil in the preferredproportions and the oil may be heated at an elevated temperature so asto cause combinations between the acids of the oil and these addedsubstances. In this way the alkylqlamines serve as purifying agents forthe oil in eliminatdng acidic bodies and at the same time convertingthem into substances which give additional valuable properties to theoil.

My oils, whether originally'produced by the addition of-the alkylamineesters, acids or the like to fresh hydrocarbon oils, or whether presentin the oil due to recovery of the used lubricating oil, find a valuableapplication as breaking-in" out. For this purpose the. oil is used inthe ordinary manner for the first 500 to 1000 miles of operation in anew car. As is well known the bearings of the car are not completelyworn in and above and when such an oil is used it is proposed to operatea new car from the high speeds and to disregard ing the breaking-in"period.

In like manner thesepour depressants may be incorporated in greases orgear oil such as transrt at relatively e usual care durmission grease toaid in reducing the tendency. to channeling and the like. 7

In the above description I have mentioned generally all types ofcombinations of the alkylolamines with fatty or other organic. acids.While. all of these materials bring about improvements in lubricatingqualities, I have observed that the true esters are more soluble andmore desirable than either the salts or the ester salts, that is to say,the materials which are both esters and 10 salts. For this reason I havea marked preference for the esters alone; Not only are they superior inrespect to tensionizing influences but also their pour reducingproperties are .markedly superior. Y

My invention is not to be limited by any theory 01'- the mechanism ofpour reduction or of "breaking-in" nor to the particular substancesdescribed for purposes of illustration, but only to the following claimsin which I wish to claim all novelty 20.

.the organic acid hasfrom 10 to 22 carbon atoms.

4. An oil according to claim 2 in'which a polyalkylolamine is used. 5. Alubricating 011 comprising a mineral oil and a minor quantity'of anester produced by the reaction of an alkylolamine and. an organic acid.

6. A mineral oil according to claim 5 in which the ester is producedfrom a polyalkylolamine.

7. An improved lubricating oil comprising a 40 viscous hydrocarbon oilcontaining a minor proportion of an ester of a trialkylolamine and anorganic acid of at least 10 carbon'atoms.

8,. An improved lubricating oil comprising a viscous hydrocarbon oilcontaining an ester produced by the reaction of triethanolamine and anorganic acid of at least 10 carbonatoms, said ester being in.tensionizing and pour inhibiting proportions.

9. An improved lubricating oil comprising a viscous waxy oil and anorganic product of the reaction of an organic acid having at least 10carbon atoms with an alkylol group of a poly- -alkylolamine intensionizing and pour reducing proportions.

10. An improved lubricating oil comprising a viscous hydrocarbon oilcontaining waxy constituents,-and an ester formed by the reaction of apolyalkylolamine and an organic acid containing at least 10 carbonatoms, said ester being in tensionizing and pour reducing proportions.

11. Lubricating oil composition comprising a viscous waxy oil containingin a dissolved state an organic product of the reaction .of analkylolamine with an organic acid having at least 10 65.

carbon atoms in pour reducing proportions. 12. Lubricating oilcomposition comprising a viscous waxy hydrocarbon 011 containing in a.

dissolved state an organic product of the reaction of a polyalkylolaminewith a fatty acid of at least ten carbon atoms in a. ur reducingproportion of not more-than abou two per cent.

13. A mineral oil composition according to claim '5 in whichsaid'organic.acid is a fatty acid.

.caaan'rou ELLIS. to

